This invention relates generally to improvements in irrigation sprinklers of the type having internal valve means for selectively turning off the water flow to an individual sprinkler spray head. More particularly, this invention relates to an improved nozzle gate valve mounted within a sprinkler spray head at the upstream side of a spray nozzle for quick and easy movement between a normal open position for substantially unobstructed water flow to and through the nozzle, and a closed position shutting off the water flow to the nozzle to accommodate facilitated nozzle removal and/or replacement or other sprinkler adjustments.
Irrigation sprinkler devices are generally known in the art to include a spray head having at least one spray nozzle through which a stream of irrigation water is projected outwardly to irrigate surrounding terrain and associated vegetation. In one common form, the sprinkler device incorporates water-powered rotary drive means for rotating the spray head about a typically vertical axis, in combination with reversing means for reversing the direction of spray head rotation in an oscillatory manner back and forth motion between adjustably set end limits or stops to sweep the water stream over an arcuate part-circle terrain area. In many sprinkler designs, the spray head is mounted at the upper end of a pop-up riser for movement between an elevated spraying position with the spray head raised above the sprinkler housing when a main system water supply is turned on, and a spring-retracted position concealed substantially within the sprinkler housing when the main system water supply is turned off. In a typical irrigation system, a common water supply conduit is coupled to multiple sprinkler devices installed within a prescribed terrain area to be irrigated, and a main control valve is turned on and off manually or by automated means for regulating water supply to the sprinkler devices.
For examples of rotary drive pop-up sprinklers of the abovedescribed general type, see U.S. Pat. Nos. 4,625,914 and 4,787,558. In addition, such rotary drive pop-up sprinklers are commercially available from Rain Bird Sprinkler Mfg. Corp. of Glendora, Calif. under the product designations T-Bird Series, R-50, Falcon, and Talon.
In many such sprinkler devices, the at least one spray nozzle mounted on the spray head is removable to accommodate installation of a selected one of a group of spray nozzles adapted to deliver irrigation water to the surrounding terrain with different spray pattern and/or flow rate or flow trajectory characteristics. Accordingly, the multiple sprinkler devices in an irrigation system can be equipped with different spray nozzles to provide a customized pattern of irrigation water delivery to the associated vegetation. As the vegetation matures, or upon replacing some or all of the plants with different vegetation, the spray nozzles associated with one or more of the sprinkler devices can be changed quickly and easily to modify the customized irrigation delivery pattern. In addition, other periodic adjustments to the sprinkler devices may be necessary or desirable, such as adjusting the reversing end limits or stops for one or more of the sprinkler devices.
In the past, sprinkler device adjustments have normally been performed while the main water supply system is turned off. For spray nozzle removal and replacement, particularly with a pop-up type sprinkler, this requires the service person to manually grasp and lift the spring-loaded riser in order to access the spray head, and then manually hold the riser in the elevated position with one hand while attempting to remove and replace the spray nozzle with the other hand. Such manipulation of the spring-loaded riser can be difficult. After the spray nozzle has been replaced, it is then necessary for the service person to access the main control valve which is often located at a remote site to turn on the water supply, and then return to the adjusted sprinkler to inspect and confirm proper operation. Such back-and-forth movement is inconvenient and time-consuming.
Some sprinkler devices have been equipped with internal flow shutoff valves to permit interruption of the water supply to the individual spray head, thereby permitting spray nozzle removal and replacement without requiring the main system water supply to be turned off. See, for example, U.S. Pat. No. 5,762,270. The inclusion of such internal shut-off valve beneficially allows the irrigation water under pressure to be supplied to the sprinkler device for displacing the pop-up riser and the spray head thereon to the elevated spraying position where the spray nozzle is readily accessible, but interrupts water flow to the spray head for convenient spray nozzle removal. Additional sprinkler adjustments such as adjustably setting the reversing end limits or stops may also be performed, all without unreasonably drenching the service person and further without requiring the service person to travel back-and-forth to the main control valve.
However, such internal shut-off valves mounted within sprinkler devices have in the past required several turns of a valve actuator in order to turn the valve on and off, thereby exposing the service person to some irrigation spray during each off-on and on-off actuation interval. Moreover, in the normal open position, such shut-off valves have presented at least some water flow obstruction and resultant pressure drop at the upstream side of the spray nozzle. This pressure drop undesirably results in a reduced maximum water flow rate through the spray nozzle.
The present invention overcomes these problems and disadvantages by providing an improved gate valve mounted within a sprinkler spray head at the upstream side of a spray nozzle for quick and easy part-turn movement between a normal open position for substantially unobstructed water flow to and through the nozzle, and a closed position shutting off the water flow to the nozzle to accommodate facilitated nozzle removal and/or replacement or other sprinkler adjustments.
In accordance with the invention, an irrigation sprinkler includes an improved nozzle gate valve for quick and easy shut-off of water flow to a sprinkler spray nozzle. The gate valve is mounted within a sprinkler spray head at an upstream side of the spray nozzle for displacement between open and closed positions respectively permitting and preventing water flow to the nozzle. An actuator pin is exposed at the top of the spray head and is adapted for part-turn movement to displace the gate valve between the open and closed positions. In the closed position, the spray nozzle can be removed and/or replaced, or other sprinkler adjustments can be performed, without requiring a main system water supply to be turned off.
In the preferred form, the gate valve has a generally conical shape seated within a matingly shaped valve pocket or chamber formed in the spray head at the upstream side of the spray nozzle. The conical gate valve defines an elbow-shaped flow path movable between the open position aligned with the spray nozzle for normal water supply thereto, and the closed position misaligned with the spray nozzle to prevent water flow thereto. The actuator pin at the top of the spray head is rotatable through a part-circle stroke of about 180xc2x0 for displacing the gate valve between the open and closed positions. In the closed position, water under pressure supplied to the sprinkler urges the gate valve into pressure-activated sealing relation with the spray head to positively seal against waterflow to the spray nozzle. The gate valve may include internal directional flow vanes formed within the elbow-shaped flow path for smooth water flow transition to the spray nozzle, when said gate valve is in the open position.
Other features and advantages of the invention will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.